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  Topic Review (Newest First)
06-22-2013 11:31 AM
Re: Shroud tension by feel

Here's some tuning tips taken from a post by a rigger on a Ranger site several years back.

When we riggers tune a rig, we put on our wizard hats and try to convince
the boatowner that it's voodoo magic that only we "experts" can achieve. The
fact is, any reasonably intelligent primate can tune a rig, and it's very
simple. This secret is only to be shared with Ranger owners, and should not
be shared with owners of lesser boats, as we still have to make a living off
all those Catalina and Beneteau owners.


1) First loosen the rig and use a main halyard or topping lift to measure
from the masthead to each side of the boat. The purpose is to center the
masthead directly over the centerline, using the upper shrouds.

2) Once centered, tighten the upper shrouds equally, making sure the
masthead stays centered.

3) Next tighten the lowers. If the boat has two sets, tighten the forward
lowers first, keeping tension equal. Attach the main halyard to the boom
tack fitting and tension the halyard. You can sight up the taut halyard to
see if the middle of the mast is bowing to the left or right of center.
Remember, the head of the mast is centered, if the mast is bowing, loosen
the lower on the "bulge" side and tighten the lower on the other side.

4) The mast should be straight athwartships and uppers and lowers tight. If
you have double lowers, the forward lowers should be tighter than the aft
lowers. If you have single lowers and a babystay, the babystay should be
tighter than the lowers. More on babystays later. The point here is that the
mid-section of the mast can be permitted to bow forward slightly, but NEVER
aft. When this is static tuned into the rig we call it "pre-bend." If your
main halyard is still attached to the tack fitting, you can use it to guage
how much pre-bend you are putting in the mast. On the masthead rigs that
most Rangers have, it should not be too much. Fractional rigs usually have
more, and can add a lot of additional bend with backstay tension.

5) Now tension the forestay and backstay. On some Rangers, such as the 28,
there is no forestay turnbuckle, just a pair of link plates with a choice of
pin positions. All the adjustment is in the backstay. The forestay can be
allowed to sag as much as 18" in light air, or set bar-tight with lots of
backstay tension for a heavy blow. Remember that on a masthead rig, the
backstay adjuster does not bend the mast very much. Its primary function is
to adjust forestay sag to power up or de-power the headsail. Put moderate
tension on the forestay if you have a good backstay adjuster.

6) The Great Rake Controversy: Very simple: Raking the mast aft increases
weather helm, raking it forward reduces it or even induces lee helm.
Excessive weather helm is bad, but lee helm is worse. A moderately straight
mast with a slight rake is right for most masthead Rangers, and you want a
slight bit of weather helm. If excess weather helm is tempting you to rake
your mast forward, then take a look at your sails, they're probably old and
baggy, and a re-cut to flatten them, or a new sail, is what you need to
correct the helm. If you feel the need to lean your mast forward, something
else is wrong.

7) Babystays: Some Rangers have adjustable babystays, often on tracks like a
traveller. Tune the rig at the dock pretty straight, but keep the tension on
the lowers minimal to allow the babystay to induce bend. Tension on the
lowers sets the limit on the bend that the babystay can create.

8) Multiple Spreaders: Applies to very few Rangers, but creates an extra
upper, or "intermediate" shroud. Simply start at the top and work down:
Uppers, intermediates, then lowers, keeping the masthead centered and the
mast straight from side to side.


Sail upwind in moderate breeze and see if the leeward shrouds sag. They
should only sag a little. Tighten the leeward shrouds HALFWAY while counting
the turns. Now tack, and tighten the other side an equal number of turns.
When satisfied that all is equal, the mast has no sidebend, and the masthead
is still on centerline at rest, then pin and tape the rig.

This is a lot of information, but static tune should take less than an hour
if all the parts are in working order. Make sure no turnbuckles are bent and
that they can articulate in all planes (toggle). Also inspect all the wires
at the point where fittings are swaged, as this is the area where failures
occur. Notice that no rigging guage is needed to tune a rig.

Remember that wire rope stretches, and on many old boats stays can stretch
to the point they cannot be tightened enough. That's when you need to
replace standing rigging, as a loose rig is dangerous. A "floppy" rig in a
blow allows shock loading that can cause other parts to fail and bring down
a rig. The biggest mistake we commonly see on boats we tune is rigs that are
way too loose. If tightening your rig loosens chainplates that were bolted
to rotten wood, you needed to fix that anyway! Best to fix it before it
makes your mast come down.
06-22-2013 10:35 AM
Re: Shroud tension by feel

Either loosen the shrouds some, tight the back stay. OR, assuming you are in PT, run the one block east to WM and get your self a loose guage and set the rig correctly according to that. THen you will know if you are loose or tight.

I remember when I bought my boat, really loose, tightened it up some. Took a loose guage to it a year or so later, found it to be in the 5-7% range. Really tightened the rig up. Along with later, shortening up the forestay and a few other things to correct weather helm etc.

06-22-2013 03:25 AM
Re: Shroud tension by feel

Hmm. I tightened the shrouds only. I think maybe too tight. Is it better to have them too tight or too loose?

I've felt boats on the dock and they are all over the place. Some super loose and some super tight. To me it seems they should be tight but what do I know. The breaking strength of 3/16" at 15% is 747 pounds. That's got to feel tight. But I don't want to fatigue my mast or deck.

Whatever I did changed the mast from a slight rake aft to foreword. What should I do to fix this?
06-06-2013 09:26 AM
Re: Shroud tension by feel

Originally Posted by northoceanbeach View Post
I know this is a hard one to answer. I just think my shrouds are too loose. In planning to get a loos gauge in the near future but to get me by about how tight should they feel.

First off my mast is in column and all standing riggin is even. So uppers feel the same etc.

Fore and back stay are pretty tight, uppers are pretty loose and lowers are really loose. So loose I can flick they and they slop around a bit.
See Hall Spars Rig Tuning Manual
06-06-2013 08:34 AM
Re: Shroud tension by feel

Originally Posted by northoceanbeach View Post
I put penetrating oil in the turnbuckles and they turned smoothly. I don't think I even needed it. I've tightened them and actually got a nice but of wind to test them out today. While sailing the leeward upper is a little tight, the aft lower is a little loose, and the foreword lower still seemed too loose. Should both lowers be about the same while sailing?

I did polish the crap out of them with bronze wool which was ass then a bristle brush and flitz metal polish.
The Leewrd Upper should be under load from the spreader by design (someone correct me if I am off base). Sight up the mast to see if it is straight, if so the upper is doing it's job. The lowers will be relaxed but not flopping around according to my research.

Disclaimer - My experience is on smaller boats, much of what I am writing is "internet knowledge" but I am trying to help
06-06-2013 12:47 AM
Re: Shroud tension by feel

I put penetrating oil in the turnbuckles and they turned smoothly. I don't think I even needed it. I've tightened them and actually got a nice but of wind to test them out today. While sailing the leeward upper is a little tight, the aft lower is a little loose, and the foreword lower still seemed too loose. Should both lowers be about the same while sailing?

I did polish the crap out of them with bronze wool which was ass then a bristle brush and flitz metal polish.
06-05-2013 12:23 PM
Re: Shroud tension by feel

Sounds like you are a bit too loose.

I would suggest tightening them each at the same small increments (half turn at a time) - it does not take much - but do them one after another and back and forth to keep the mast as straight as possible. You could even grab your binoculars if you have them and stand far way on shore and try to sight how straight the mast is. Go back, do it again to get the correct balance and desired tension.

You could just go to the boats that are in tip-top shape and go sailing often and made yours the same feeling tension.

While you're at it, a cheap bristle brush along the shroud wires is good to clean out the dust and dirt, and also a bottle of turnbuckle lube (like $5 at marine store for a tiny bottle the size of crazy glue) and a few drops on each will make you feel confident about it before you start tightening things.
06-05-2013 09:49 AM
Alex W
Re: Shroud tension by feel

New rigging is more like several hundred on a Ranger 23. It's a lot cheaper when you have shorter and smaller diameter wire.

This is what Catalina suggests for rigging tension on a Catalina 25 (3/16" uppers):
The upper shrouds should be firm but not tight. A 50 pound push should deflect the upper shroud about 1" at shoulder height.

Not as accurate as a Loos Gauge, but pretty simple to check.

If I remember correctly the book "Sail and Rig Tuning" does have methods for accurately measuring rig tension without using a Loos Gauge. I think you'll find this at many marine stores.
06-05-2013 09:44 AM
Re: Shroud tension by feel

A Loos gauge is about 100 bucks. New rigging is several thousand.

I've got a 90b I got for my last boat, wouldn't you know not one of the wires on my Irwin is small enough and now I've got to get a 90a or the professional version?
06-05-2013 09:38 AM
Re: Shroud tension by feel

My stbd lowers were flapping on a port tack this weekend so I started searching as well. I just tightened them a couple of turns and will go out and check them. As was stated, under sail the leeward lowers should not flop around but relax a bit.

Thinking about it...I went one turn only. it doesn't take much
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